Polishing solution recycling apparatus

Abstract

The invention discloses a polishing solution recycling apparatus. The apparatus comprises a storage tank, a power supply, a first circulating pump and a degasser. The storage tank is used for storing a polishing solution, and an anode plate and a cathode plate are arranged in the storage tank. The anode of the power supply is electrically connected with the anode plate, and the cathode of the power supply is electrically connected with the cathode plate. The inlet of the first circulating pump is connected with the bottom of the storage tank, the outlet of the first circulating pump is connected with the liquid inlet of the degasser, the liquid outlet of the degasser is connected with the top of the storage tank, and the degasser can remove bubbles in the polishing solution. The arrangement of the degasser realizes the removal of the bubbles in the polishing solution. The improvement of the copper ion separation rate due to the increase of the current and voltage output of the power supply during electrolysis has no influences on the reuse of the polishing solution; and the apparatus runs in a cycle manner, and avoids outward waste liquid emission, so the apparatus does not pollute the environment, saves raw materials and reduces the process cost.

Description

technical field [0001] The invention relates to the technical field of integrated circuit manufacturing, in particular to a polishing liquid recycling device. Background technique [0002] As a strategic, basic and leading industry for national economic and social development, the integrated circuit industry has strong innovation and integration capabilities, and has penetrated into all aspects of people's life, production and national defense security. As the scale of the integrated circuit industry continues to expand, the demand for raw materials for manufacturing integrated circuits is also increasing. [0003] For example, in the manufacturing process of copper interconnection of integrated circuits, the polishing liquid is used to remove redundant copper structures. Based on the principle of electrochemical polishing, only the polishing liquid is in contact with the silicon wafer, thereby removing the redundant copper structures on the silicon wafer without stress. Us...

AI Technical Summary

Problems solved by technology

When the polishing liquid treated with copper recycling is used for copper polishing again, the bubbles in the polishing liquid will adhere to the surface of the silicon wafer, which will change the current density on the surface of the silicon wafer, thus causing the surface finish of the silicon wafer to deteriorate , in the case of high polishing process requirements, this kind of polishing liquid is not available, and if the polishing liquid is directly discharged, it will not only cause environmental pollution, but also cause waste of raw materials, resulting in increased production costs. In a fierce market, this method is obviously not advisable

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